Means for controlling fluid-pressure.



PATENTED NOV. 12, 1907.

F. E. KINSMAN. MEANS FOR CONTROLLING FLUID PRESSURE.

APPLICATION FILED DEO.17. 1901.

UNITED STATES PATENT orricn.

FRANK E. KINSMAN, OF PLAINFIELD, NEW JERSEY.

MEANS FOR CONTROLLING FLUID-PRESSURE.

To all whom it may concern:

Be it known that I, FRANK E. KINSMAN, a citizen of the United States,and a resident of Plainfield', in the county of Union and State of NewJersey, have invented certain new and useful Improvements in Means forControlling Fluid-Pressure, of which the following is aspecification.

This invention relates to means for controlling fluid pressure, andespecially to a brake system for automatically varying the pumpingaction as the pressure developed in the system by a pump increases ordecreases, the main object of the invention being to reduce or stop thework done by the pump as the pressure therein, or in the systemcontrolled thereby, approaches or attains the desired value, andparticularly to reduce the stroke of the pump gradually from maximum tozero, and increase the same from zero to maximum stroke, as the pressurein the pump, or in the fluidpressure system in communication therewith,rises from atmospheric pressure to the desired maximum or falls from themaximum to atmospheric pressure.

Automatic pressure-regulating apparatus of this type is especiallyadapted for use in connection with fluidpressure brakes controlled bypressure in a system governed by a pump operated from acontinuously-rotatable driver, such as an axle of a vehicle or trainmovable along a line of way or railway, for the reason that when thepressure in the fluid-pressure brake system is controlled by a pumpoperated from a continuously-rotatable axle in accordance with myinvention the operation of the pump may be varied automatically, inaccordance with the requirements of the system, without regard to thecontinuous rotation of the axle from which power is derived. This is avery important feature in actual practice. as in ordinary fluid-pressurebrake systems. the pumps of which are operated from thecontinuously-rotating axles of the train there is excessive strain oneach of the pumps. due to the fact that it has to make its full strokeand exert its maximum pumping effect at each operation, regardless ofthe fact that the limit of pressure,

either compression or vacuum, may have been attained. As the fullworking effect has to be exerted at each stroke in the systems now inuse there is also unnecessarywear on the operating parts'. excessivevibration and noise due to the movements of these parts and excessivenoise due to the hissing consequent upon the escape or inrush of airwhen the maximum pressure is reached and an automatic safety-valvecommon to such systems is opened to permit the escape of excessivepressure of compressed air or the inrush of air to reduce a vacuum toohighly attenuated.

Specification of Letters Patent.

Patented Nov. 12, 1907.

Application fild December 17} 1901. Serial No. 86.312.

shown a fluid-pressure brake system embodying an automaticpressure-controlling apparatus illustrating one embodiment of myinvention.

The construction shown illustrates one way in which the pumping actionmay be varied, power saved, and excessive wear' on and straining of thepump avoided, in a fluid-pressure brake system the pressure in which isgoverned by a pump operated from a continuouslyrotatable driver. Theparticular mode in which the pressure-developing operation is varied inthe construction shown. is by varying the stroke of the compressorbetween given maximum and minimum points, and especiall y by varying thestroke of the pump-piston from maximum to zero, it being evident that insuch an embodiment of the invention, while the piston will be enabled tomake its maximum stroke at the proper times, its operation may cea-seentirely when the maximum compression or vacuum is attained, and thiswithout affecting at all the continuous rotation of the driver or axlefrom which the pump-piston derives its movement.

The pump by means of which compression or exhaustion is produced may beof any usual type, and I have illustrated herein an ordinary force-pumpor compressor 2, the piston of which is designated by 3, and

the piston-rod by 4, this latter being preferably movable through aguide 5, while the piston and the casing of the pump 2 have the ordinaryinlets 6 and 7, the former of which may be closed by the valve 8. As airis drawn into the pump 2 and compressed therein it may be delivered intoany suitable chamber or receiver therefor, such as that illustrated at10, which may be connected by a pipe 11, with the compression side ofthe pump, and in this instance constitutes the main air reservoir of acompressed-air brake system. The work done by the pump is intended to bevaried in accordance with the pressure on the compression side thereof,that is to say, in accordance with the pressure, in this instance, inthe main chamber or reservoir 10, and this regulating action should varyas the pressure in said reservoir rises or falls, and hence thepressuredeveloping operation of the pump, which in this case is thestroke of its piston, should also vary as such pressure rises or falls.In compressed-air brake systems it is customary to force thecompressed-air from the main chamber 10 through a pipe 12 into anothermain chamber 13 constituting a dry'air chamber, or reservoir, and toconnect the train-pipe of the system directly with this dry-air chamber,and such is the construction shown herein, the train-pipe in this casebeing designated by 14, and being connected to one arm of a Y- coupling15, while a pipe 16, may lead from the other arm of this coupling to theprimary elemer ,of the fluidpressure regulator. Pressure in the systemmay be controlled by an ordinary three-way valve, such as 17 to the stemof which is connected the usual manual controller or engineersbrake-handle 18, by means of which communication may be kept openbetween the train-pipe l4 and a pipe 19, leading toa. brake-controllingchamber 20, or closed to the pipe 14 and opened between the pipe 19 andthe usttal outlet pipe 21, it; being understood that when the pressurein the chamber 20 is allowed to escape a brake, such as 22, will beoperated, this brake being connected, in the present construction. withthe piston-rod 23 by toggle-cams 24.

The pipe it; is intended to communicate with one end of a regulatingchamber such as 25. having therein a piston 26 movable back and forth.one side of such piston being in connnunication. as is evident, with themain chamber connected with the pump. while the piston may be operatedin the other direction by a. counteracting force at that side of thepiston opposite such point of communication with the main chamber, aspring 27 being preferably employed for counteracting such tlnidpressure. The movement, of the piston 26 is the preferred means employedfor controlling the operatlon, or working stroke. of the pump, by meansof which pressure in the system is produced and maintained. and thismovement may be transmitted in any suitable manner for aecoltiplisliinga regulation of the pumping action varying in accordance with, orproportional to. variations in the pressure in the system. or in thepump by means of which pressure in the system is developed. 1 deem itdesirable, however, to transmit the movement of this piston to amechanical element or intermediate having a movement of variableeliiciency. such as a lever having a variable leverage controlled by themovement of said piston, and in the construction shown the. piston has along piston-rod 28, movable in suitable guides, such as 29, and hencehaving a simple movement in a straight line, and this pistolidotlsupports, and hence serves to shift, the pivot of a lever 30, one end ofwhich lever is connected to suitable actuating means, such as aneccentric-rod 31, carried by an eccentric 32, secured to acontinuously-ro talable driver, or car-axle, 33. while at its other endthe lever 30 may be connected to a link 34, pivoted to the piston-rod 4.it willbenoticed that the upper end of the lever 30 is continued somedistance beyond theextreme load-point thereof, and that the link 34 ispivoted to the auxiliary portion 30 of said lever, this constructionbeing employed in order to enable a guide, such as 35. whit-his pivotedon the piston-rod 28, and in which the lever 30 is pi\ oted, to moveback and forth on said lever and to pass beyond the extreme minimumloadpoint to the point of-no load. which is coincident with the fulcrumof said lever at the zero-point of leverage, that is. at the point wherethe pump-piston has no stroke while the axle 33 may be continuouslyrotating at a rapid rate of speed. The member 35 is preferably a sleevepivoted in a fixed position on the piston-rod 28 and turns with thelever 30 in order to accommodate itself to the movement of said lever asthe latter turns in the sleeve and also as the sleeve moves along saidlover, and shifts the fulcrum-point oi the same to shorten or lengthenthe st rokc of said lever.

The amount of pressure in the system may be indicated at some suitablepoint, as for example, at the regulating-chamber 25, by means of a gage36, in comrnunication therewith.

I may also provide, for the purpose of supplementing the automaticregulation of the pumping action, a handoperated device for determiningthe stroke of the pump, a. nut 37 for varying the tension of the spring27 being employed herein for this purpose.

What I claim is: I

1. The combination with a compressed-air brake; of a compressed-airsystem governing the operation of said brake and embodying a compressorhaving a variable stroke. a reservoirya train-pipe leading from saidreservoir. a brake-pipe. an air outlet. a three-way valve for connectingsaid brake-pipe with the train-pipe or the airoutlet to admit pressureinto the brake-pipe or release the pressure therein. a. regulatingchamber having a piston one side of which is in communication with saidtrainpipe. and a regulating spring at tile other side of said piston:and means movable in correspondence with said piston and with thevariable pressure exerted by the spring, and controlled by the movementof said piston consequent on the closing or openim. of communicationbetween the train-pipe and the brake-pipe by said three-way valve, forshortening or lengthening the stroke of the compressor at any pointbetween maximum and minimum and thereby regulating the pressure in saidtrain-pipe and brake-pipe.

2. 'lhecombination with a compressed-air brake; of a 'compressed-airsystem governing the operation of said brake and embodying a compressorhaving a variable stroke. a reservoir. :1 trninpipe, a brakc'pipe, anair-outlet, controlling means for connecting said brake-pipe with thepressure in the system or the air-outlet to :Ulmit pressure into thebrake-pipe or release the pressure therein, a regulating chamber havinga piston one side of which is in communication with the pressure in thesystem. and a regulating spring at the other side of said piston: andmeans movable in corres iondence with said piston and with the 'ariublepressure exerted by the spring. and controlled bythe movement of saidpiston consequent on the closing or opening of eoinlnuniealion betweenthe pressure in the system and the brnke-pipe by said controlling means,for shortening or lengthening the stroke of the compressor at any pointbetween maximum anti mininnnn and thereby regulating the pressure insaid system and brake-pipe.

.i. The combination with a fluid-pr ssure brake. of a fluidpressuresystem governing the operation of said brake and embodying a pump, aspring opposing such fiuid-pressure. a reciprm-alory controlling membersubjected both to said thud-pressure and to said spring pressure antiactuated by the dilierence in pressure between said iluid 'n'essure andsaid spring pressure, and means governed by said control iin; member andmovable in cor-res iondence therewith and with the variable pressureexerted by the spring for so varying the pumpin; action at any pointbetween maximum and minimum as to constantly tend to maintain the normalfluid-pressure in the system for governing the brake.

4. The combination 'ill] a compressed-atr brake. of a compressed-airsystem governing the operation of said brake anti embodying acompressor, a spring opposing such air-pressure. a reclprmratorycontrolling member subjected both to said air-pressure and to saidspring pressure and actuated by the dilference in pressure between saidairpressure and said spring pressure, and means governed by saidcontrolling member and movable in correspondence therewith and with thevariable pressure exerted by the spring for so varying the compressingaction at any point between maximum and minimum as to constantly tend tomaintain the air-pressure necessary for releasing said brake.

Signed at New York in the county of New York, and State of New York this13th day of December, A. l). 1901.

FRANK E. KINSMAN.

Witnesses (f. 5. Cnanmox, R. CHAMPION.

